Semiconductor Processing System Having Multiple Decoupled Plasma Sources

ABSTRACT

A semiconductor substrate processing system includes a substrate support defined to support a substrate in exposure to a processing region. The system also includes a first plasma chamber defined to generate a first plasma and supply reactive constituents of the first plasma to the processing region. The system also includes a second plasma chamber defined to generate a second plasma and supply reactive constituents of the second plasma to the processing region. The first and second plasma chambers are defined to be independently controlled.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is related to U.S. patent application Ser. No. ______(Attorney Docket No.: LAM2P705B), filed on an even date herewith, andentitled “Semiconductor Processing System Having Multiple DecoupledPlasma Sources,” which is incorporated herein by reference in itsentirety.

BACKGROUND OF THE INVENTION

Plasma sources utilized for thin film processing in semiconductor devicefabrication are often unable to achieve the most desirable condition fordry etching due to the inability to separately control ion and radicalconcentrations in the plasma. For example, in some applications, thedesirable conditions for plasma etching would be achieved by increasingthe ion concentration in the plasma while simultaneously maintaining theradical concentration at a constant level. However, this type ofindependent ion concentration versus radical concentration controlcannot be achieved using the common plasma source typically used forthin film processing. It is within this context that the presentinvention arises.

SUMMARY OF THE INVENTION

In one embodiment, a semiconductor substrate processing system isdisclosed. The system includes a substrate support defined to support asubstrate in exposure to a processing region. The system also includes afirst plasma chamber defined to generate a first plasma and supplyreactive constituents of the first plasma to the processing region. Thesystem also includes a second plasma chamber defined to generate asecond plasma and supply reactive constituents of the second plasma tothe processing region. The first and second plasma chambers are definedto be independently controlled.

In another embodiment, a semiconductor substrate processing system isdisclosed. The system includes a chamber having a top structure, abottom structure, and sidewalls extending between the top and bottomstructures. The chamber encloses a processing region. A substratesupport is disposed within the chamber and defined to support asubstrate in exposure to the processing region. The system also includesa top plate assembly disposed within the chamber above the substratesupport. The top plate assembly has a lower surface exposed to theprocessing region and opposite the top surface of the substrate support.The top plate assembly includes a first plurality of plasma portsconnected to supply reactive constituents of a first plasma to theprocessing region. The top plate assembly also includes a secondplurality of plasma ports connected to supply reactive constituents of asecond plasma to the processing region.

In another embodiment, a method is disclosed for processing asemiconductor substrate. The method includes an operation for placing asubstrate on a substrate support in exposure to a processing region. Themethod also includes an operation for generating a first plasma of afirst plasma type. The method also includes an operation for generatinga second plasma of a second plasma type different than the first plasmatype. The method further includes an operation for supplying reactiveconstituents of both the first and second plasmas to the processingregion to affect a processing of the substrate.

Other aspects and advantages of the invention will become more apparentfrom the following detailed description, taken in conjunction with theaccompanying drawings, illustrating by way of example the presentinvention.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows relationships between ion concentration and radicalconcentration achievable with use of multiple plasma chambers inexposure to a common substrate processing region, in accordance with oneembodiment of the present invention;

FIG. 2A shows a semiconductor substrate processing system, in accordancewith one embodiment of the present invention;

FIG. 2B shows a semiconductor substrate processing system, in accordancewith one embodiment of the present invention;

FIG. 2C shows a semiconductor substrate processing system, in accordancewith one embodiment of the present invention;

FIG. 2D shows a variation of the second plasma chamber having anenergized outlet region to enhance ion extraction, in accordance withone embodiment of the present invention;

FIG. 2E shows a variation of the system in which the first and secondplasma chambers are separated by a dielectric material, in accordancewith one embodiment of the present invention;

FIG. 2F-1 shows another variation of the system of FIG. 2A in which thepower delivery components of the first and second plasma chambers areimplemented as electrodes disposed within the first and second plasmachambers, in accordance with one embodiment of the present invention;

FIG. 2F-2 shows another variation of the system of FIG. 2A in which thepower delivery components of the first and second plasma chambers areimplemented as electrodes disposed on upper and lower surfaces withinthe first and second plasma chambers, in accordance with one embodimentof the present invention;

FIG. 2G shows another variation of the system of FIG. 2A in which thepower delivery components of the first and second plasma chambers areimplemented as coils disposed proximate to the first and second plasmachambers, in accordance with one embodiment of the present invention;

FIG. 3A shows a vertical cross-section of a semiconductor substrateprocessing system, in accordance with one embodiment of the presentinvention;

FIG. 3B shows a horizontal cross-section view A-A as referenced in FIG.3A, in accordance with one embodiment of the present invention;

FIG. 3C shows a variation of the horizontal cross-section view of FIG.3B in which the spacing between the first and second plasmamicrochambers across the top plate assembly is decreased, in accordancewith one embodiment of the present invention;

FIG. 3D shows a variation of the horizontal cross-section view of FIG.3B in which the spacing between the first and second plasmamicrochambers across the top plate assembly is increased, in accordancewith one embodiment of the present invention;

FIG. 3E shows a variation of the horizontal cross-section view of FIG.3B in which the spacing between the first and second plasmamicrochambers across the top plate assembly is non-uniform, inaccordance with one embodiment of the present invention;

FIG. 4A shows another system for substrate plasma processing, inaccordance with one embodiment of the present invention;

FIG. 4B shows a horizontal cross-section view B-B as referenced in FIG.4A, in accordance with one embodiment of the present invention;

FIG. 4C shows a variation of the horizontal cross-section view of FIG.4B in which the spacing between the plasma ports associated with thefirst and second plasma chambers across the top plate assembly isdecreased, in accordance with one embodiment of the present invention;

FIG. 4D shows a variation of the horizontal cross-section view of FIG.4B in which the spacing between the plasma ports associated with thefirst and second plasma chambers across the top plate assembly isincreased, in accordance with one embodiment of the present invention;

FIG. 4E shows a variation of the horizontal cross-section view of FIG.4B in which the spacing between the plasma ports associated with thefirst and second plasma chambers across the top plate assembly isnon-uniform, in accordance with one embodiment of the present invention;

FIG. 5A shows another system for substrate plasma processing, inaccordance with one embodiment of the present invention;

FIG. 5B shows a horizontal cross-section view C-C as referenced in FIG.5A, in accordance with one embodiment of the present invention;

FIG. 5C shows a variation of the horizontal cross-section view of FIG.5B in which the spacing between the first and second sets of plasmamicrochambers across the lower surface of the top plate assembly isdecreased, in accordance with one embodiment of the present invention;

FIG. 5D shows a variation of the horizontal cross-section view of FIG.5B in which the spacing between the first and second sets of plasmamicrochambers across the lower surface of the top plate assembly isincreased, in accordance with one embodiment of the present invention;

FIG. 5E shows a variation of the horizontal cross-section view of FIG.5B in which the spacing between the first and second sets of plasmamicrochambers across the lower surface of the top plate assembly isnon-uniform, in accordance with one embodiment of the present invention;

FIG. 6 shows a flowchart of a method for processing a semiconductorsubstrate, in accordance with one embodiment of the present invention;and

FIG. 7 shows a flowchart of a method for processing a semiconductorsubstrate, in accordance with one embodiment of the present invention.

DETAILED DESCRIPTION

In the following description, numerous specific details are set forth inorder to provide a thorough understanding of the present invention. Itwill be apparent, however, to one skilled in the art that the presentinvention may be practiced without some or all of these specificdetails. In other instances, well known process operations have not beendescribed in detail in order not to unnecessarily obscure the presentinvention.

Various embodiments of the present invention include two or more typesof plasma generating devices, such as plasma chambers, that can beindependently operated using separate control parameters in order toachieve decoupled control of ion and radical concentrations within aplasma processing region to which the two or more types of plasmagenerating devices are fluidly connected, with a substrate to beprocessed disposed within the plasma processing region. For example, inone embodiment, a first plasma chamber can be operated to generate afirst plasma that has a higher radical concentration than ionconcentration. Also, in this example embodiment, a second plasma chambercan be operated to generate a second plasma that has a higher ionconcentration than radical concentration. Both the first and secondplasma chambers are fluidly connected to a same substrate processingregion, such that the first plasma chamber is operated to control anamount of radical constituents within the substrate processing region,and such that the second plasma chamber is operated to control an amountion constituents within the substrate processing region. In this manner,the first plasma chamber is controlled to tune the ion concentration inthe substrate processing region, and the second plasma chamber iscontrolled to tune the radical concentration in the substrate processingregion.

In one embodiment, the term “substrate” as used herein refers to asemiconductor wafer. However, it should be understood that in otherembodiments, the term “substrate” as used herein can refer to substratesformed of sapphire, GaN, GaAs or SiC, or other substrate materials, andcan include glass panels/substrates, metal foils, metal sheets, polymermaterials, or the like. Also, in various embodiments, the “substrate” asreferred to herein may vary in form, shape, and/or size. For example, insome embodiments, the “substrate” as referred to herein may correspondto a 200 mm (millimeters) semiconductor wafer, a 300 mm semiconductorwafer, or a 450 mm semiconductor wafer. Also, in some embodiments, the“substrate” as referred to herein may correspond to a non-circularsubstrate, such as a rectangular substrate for a flat panel display, orthe like, among other shapes. The “substrate” referred to herein isdenoted in the various example embodiment figures as substrate 105.

Independent operation of multiple plasma chambers to provide reactiveconstituents to a common substrate processing region provides forsubstantially decoupled adjustment of ion concentration relative toradical concentration within the common substrate processing region. Invarious embodiments, generation of the different types of plasmas withinthe multiple plasma chambers is achieved through independent control ofthe power supplies and/or gas supplies associated with the multipleplasma chambers. Also, in some embodiments, outputs of the multipleplasma chambers can be disposed in a spatial array in fluidcommunication with the substrate processing region. The outputs of themultiple plasma chambers can be interspersed with each other and spacedin sufficiently close proximity to each other, such that the differentreactive constituents of the different types of plasmas formed withinthe multiple plasma chambers are supplied to the substrate processingregion in a substantially uniform manner so as to affect a substantiallyuniform processing of a substrate within the substrate processingregion.

FIG. 1 shows relationships between ion concentration and radicalconcentration achievable with use of multiple plasma chambers inexposure to a common substrate processing region, in accordance with oneembodiment of the present invention. A first line 301 shows a variationof ion concentration versus radical concentration in a first plasmagenerated in a first plasma chamber in fluid connection to the commonsubstrate processing region. In this example the first plasma has ahigher radical concentration than ion concentration. A second line 303shows a variation of ion concentration versus radical concentration in asecond plasma generated in a second plasma chamber in fluid connectionto the common substrate processing region. In this example the secondplasma has a higher ion concentration than radical concentration.Therefore, the first plasma is generated to primarily supply radicalconstituents to the substrate processing region, and the second plasmais generated to primarily supply ion constituents to the substrateprocessing region.

Through independent control of the first and second plasma chambers,essentially any ion concentration versus radical concentration withinthe domain extending between the first line 301 and the second line 303is achievable within the substrate processing region. For example, thesecond plasma chamber can be operated alone to supply a firstion-to-radical concentration ratio 305 within the substrate processingregion. When used together, the first plasma chamber can be operated toincrease the radical concentration within the substrate processingregion while the second plasma chamber is operated to maintain asubstantially steady ion concentration within the substrate processingregion, thereby creating a second ion-to-radical concentration ratio 307within the substrate processing region that is not achievable witheither the first or second plasma chamber alone. Similarly, when usedtogether, the second plasma chamber can be operated to decrease the ionconcentration within the substrate processing region while the firstplasma chamber is operated to maintain a substantially steady radicalconcentration within the substrate processing region, thereby creating athird ion-to-radical concentration ratio 309 within the substrateprocessing region that is not achievable with either the first or secondplasma chamber alone.

Further with regard to FIG. 1, the first plasma chamber can be operatedalone to supply a fourth ion-to-radical concentration ratio 311 withinthe substrate processing region. When used together, the second plasmachamber can be operated to increase the ion concentration within thesubstrate processing region while the first plasma chamber is operatedto maintain a substantially steady radical concentration within thesubstrate processing region, thereby creating a fifth ion-to-radicalconcentration ratio 313 within the substrate processing region that isnot achievable with either the first or second plasma chamber alone.Similarly, when used together, the first plasma chamber can be operatedto decrease the radical concentration within the substrate processingregion while the second plasma chamber is operated to maintain asubstantially steady ion concentration within the substrate processingregion, thereby creating a sixth ion-to-radical concentration ratio 315within the substrate processing region that is not achievable witheither the first or second plasma chamber alone.

Based on the foregoing, it should be understood that in one embodimentof the present invention multiple independently controlled plasmachambers are used to supply reactive constituents to a common substrateprocessing region, so as to provide ion-to-radical concentration ratioswithin the substrate processing region that are not achievable throughoperation of a single plasma chamber alone. Based on the discussion withregard to FIG. 1, it should be further appreciated that generation ofmultiple plasmas having significantly different ion-to-radicalconcentration ratios provides for a broader range of ion-to-radicalconcentration ratio within the substrate processing region when thereactive constituents of the multiple plasmas are combined. A number ofsemiconductor substrate processing systems are disclosed herein thatprovide for spatial combination of reactive constituent outputs frommultiple independently controlled plasma chambers to create acombination of reactive constituents within a substrate processingregion that is not achievable with a single plasma chamber alone.

FIG. 2A shows a semiconductor substrate processing system 200A, inaccordance with one embodiment of the present invention. The system 200Aincludes a substrate support 107 defined to support a substrate 105 inexposure to a processing region 106. The system 200A also includes afirst plasma chamber 101 defined to generate a first plasma 101A andsupply reactive constituents 108A of the first plasma 101A to theprocessing region 106 through an opening in the first plasma chamber101. The system 200A also includes a second plasma chamber 102 definedto generate a second plasma 102A and supply reactive constituents 108Bof the second plasma 102A to the processing region 106 through anopening in the second plasma chamber 102. The first plasma chamber 101and the second plasma chamber 102 are defined to be independentlycontrolled.

More specifically, the first plasma chamber 101 is electricallyconnected to a first power supply 103A. The first power supply 103A isdefined to supply a first power to the first plasma chamber 101. Thefirst plasma chamber 101 is also fluidly connected to a first processgas supply 104A defined to supply a first process gas to the firstplasma chamber 101. The first plasma chamber 101 is defined to apply thefirst power to the first process gas to generate the first plasma 101Awithin the first plasma chamber 101.

The second plasma chamber 102 is electrically connected to a secondpower supply 103B. The second power supply 103B is defined to supply asecond power to the second plasma chamber 102. The second plasma chamber102 is also fluidly connected to a second process gas supply 104Bdefined to supply a second process gas to the second plasma chamber 102.The second plasma chamber 102 is defined to apply the second power tothe second process gas to generate the second plasma 102A within thesecond plasma chamber 102.

It should be understood that depending on the power applied and processgas used, the first and second plasma chambers 101/102 can generatesignificantly different types of plasmas 101A/102A. In one embodiment,the first and second power supplies 103A/103B are independentlycontrollable. Also, in one embodiment, the first and second process gassupplies 104A/104B are independently controllable. And, in anotherembodiment, both the first and second power supplies 103A/103B and thefirst and second process gas supplies 104A/104B are independentlycontrollable.

It should be understood that independent control of the first and secondprocess gas supplies 104A/104B can be with regard to one or more of gastype/mixture, gas flow rate, gas temperature, and gas pressure, amongessentially any other process gas related parameter. Also, it should beunderstood that independent control of the first and second powersupplies 103A/103B can be with regard to one or more of radiofrequency(RF) amplitude, RF frequency, voltage level, and current level, amongessentially any other power related parameter.

In one embodiment, the first power supplied by the first power supply103A to the first plasma chamber 101 is either direct current (DC)power, RF power, or a combination of DC and RF power. Similarly, in oneembodiment, the second power supplied by the second power supply 103B tothe second plasma chamber 102 is either DC power, RF power, or acombination of DC and RF power. In one embodiment, the first powersupplied by the first power supply 103A to the first plasma chamber 101is RF power having a frequency of either 2 megaHertz (MHz), 27 MHz, 60MHz, 400 kiloHertz (kHz), or a combination thereof, and the second powersupplied by the second power supply 103B to the second plasma chamber102 is RF power having a frequency of either 2 MHz, 27 MHz, 60 MHz, 400kHz, or a combination thereof. In one version of this embodiment, thefrequencies of the first and second powers are different. However, inanother version of this embodiment, the frequencies of the first andsecond powers can be the same if the process gases supplied to the firstand second plasma chambers 101/102 provide for differentiation betweenthe first and second plasmas 101A/102A.

The type of power applied to first and second plasma chambers 101/102 ispartially dependent upon the type of plasma chamber used. In someexample embodiments, each of the first and second plasma chambers101/102 is either a hollow cathode chamber, or an electron cyclotronresonance chamber, or a microwave driven chamber, or an inductivelycoupled chamber, or a capacitively coupled chamber. Also, in oneembodiment, the first and second plasma chambers 101/102 are the sametype of plasma chamber. However, in another embodiment, the first andsecond plasma chambers 101/102 are different types of plasma chambers.

Also, it should be understood that in different embodiments the firstand second plasma chambers 101/102 can include different forms of powerdelivery components. The power delivery components are responsible forconveying the power to the process gas inside the first/second plasmachamber 101/102. For example, in one embodiment, the walls of thefirst/second plasma chamber 101/102 are electrically conductive andserve the function of the power delivery components. In this embodiment,the first and second plasma chambers 101/102 can be separated from eachother by dielectric material and a conductive shield to ensure thatpower delivered to one plasma chamber 101/102 is not adversely receivedby a neighboring plasma chamber 101/102. FIG. 2E shows a variation ofthe system 200A in which the first and second plasma chambers 101/102are separated by a conductive shield 151 disposed between dielectricmaterial 150, in accordance with one embodiment of the presentinvention. In one embodiment, the conductive shield 151 is electricallyconnected to a reference ground potential.

FIGS. 2F-1 and 2F-2 show another variation of the system 200A of FIG. 2Ain which the power delivery components of the first and second plasmachambers 101/102 are implemented as electrodes 160 disposed within thefirst and second plasma chambers 101/102, in accordance with oneembodiment of the present invention. FIG. 2F-1 shows an exampleembodiment in which the electrodes 160 are placed on sidewalls of thefirst and second plasma chambers 101/102. FIG. 2F-2 shows an exampleembodiment in which the electrodes 160 are placed on the upper and lowersurfaces within the interior of the first and second plasma chambers101/102. In this embodiment, the electrode 160 on the upper surfacewithin the interior of the plasma chambers 101/102 includes one or moreholes defined therethrough to enable fluid communication of the firstand second process gas supplies 104A/104B with the interior volume ofthe first and second plasma chambers 101/102, respectively. Also, inthis embodiment, the electrode 160 on the lower surface within theinterior of the first and second plasma chambers 101/102 includes one ormore holes defined therethrough to enable passage of the reactiveconstituents of the first and second plasmas 101A/102A, respectively, tothe processing region 106. It should be understood that the placementsof the electrodes 160 in FIGS. 2F-1 and 2F-2 are shown by way ofexample. In other embodiments, the electrodes 160 can be disposed on anyone or more surfaces within the plasma generation volume of thefirst/second plasma chamber 101/102.

FIG. 2G shows another variation of the system 200A of FIG. 2A in whichthe power delivery components of the first and second plasma chambers101/102 are implemented as coils 170 disposed proximate to the first andsecond plasma chambers 101/102, in accordance with one embodiment of thepresent invention. It should be understood that the top placement of thecoils 170 in FIG. 2G is shown by way of example. In other embodiments,the coils 170 can be disposed proximate to any one or more outersurfaces of the first/second plasma chamber 101/102. It should beunderstood that the different power delivery component embodiments ofFIGS. 2A, 2E, 2F, and 2G are shown by way of example. In otherembodiments, the first and second plasma chambers 101/102 can implementpower delivery components different than those exemplified in FIGS. 2A,2E, 2F, and 2G.

Given the foregoing, it should be understood that the first and secondplasma chambers 101/102 can be operated using different process gasesand/or different powers in order to achieve a condition in which oneplasma provides a higher concentration of ions relative to radicals, andin which the other plasma provides a higher concentration of radicalsrelative to ions. Also, the first and second plasma chambers 101/102 aredefined to respectively distribute the reactive constituents 108A/108Bof the first and second plasmas 101A/102A in a substantially uniformmanner within the processing region 106 above the substrate support 107.

In one embodiment, the first and second plasma chambers 101/102 aredefined to operate at internal pressures up to about one Ton (T). Also,in one embodiment, the processing region 106 is operated within apressure range extending from about 1 milliTorr (mT) to about 100 mT.The outlets of the first and second plasma chambers 101/102 are definedto provide and control the pressure drop between the interiors of thefirst and second plasma chambers 101/102 and the processing region 106.Also, if necessary, in one embodiment, the radical constituents can besupplied from either one of the first and second plasma chambers 101/102in a cross-flow arrangement, or use cross-flow within the processingregion 106, to manage etch product distribution across the substrate105.

In one example embodiment, the system 200A is operated to provide aprocessing region 106 pressure of about 10 mT, with a process gasthroughput flow rate of about 1000 scc/sec (standard cubic centimetersper second), and with a reactive constituent 108A/108B residence timewithin the processing region 106 of about 10 milliseconds (ms). Itshould be understood and appreciated that the above example operatingconditions represent one of an essentially limitless number of operatingconditions that can be achieved with the system 200A. The above exampleoperating conditions do not represent or imply any limitation on thepossible operating conditions of the system 200A.

In one embodiment, the substrate support 107 is defined to be movable ina direction 110 substantially perpendicular to a top surface of thesubstrate support 107 upon which the substrate 105 is to be supported,thereby enabling adjustment of a process gap distance 113. The processgap distance 113 extends perpendicularly between the top surface of thesubstrate support 107 and the first and second plasma chambers 101/102.In one embodiment, the substrate support 107 is movable in the direction110 such that the process gap distance is adjustable within a rangeextending from about 2 cm to about 10 cm. In one embodiment, thesubstrate support 107 is adjusted to provide a process gap distance 113of about 5 cm. In an alternate embodiment, adjustment of the process gapdistance 113 can be achieved through movement of the first and secondplasma chambers 101/102 in the direction 110 relative to the substratesupport 107.

Adjustment of the process gap distance 113 provides for adjustment of adynamic range of the ion flux emanating from either or both of the firstand second plasma chambers 101/102. Specifically, the ion flux thatreaches the substrate 105 can be decreased by increasing the process gapdistance 113, vice versa. In one embodiment, when the process gapdistance 113 is adjusted to achieve and adjustment in the ion flux atthe substrate 105, the process gas flow rate through the higherradical-supplying plasma chamber (101/102) can be adjusted to providefor independent control of the radical flux at the substrate 105.Additionally, it should be appreciated that the process gap distance 113in combination with the ion and radical fluxes emanating from the firstand second plasma chambers are controlled to provide for a substantiallyuniform ion density and radical density at the substrate 105.

In one embodiment, the substrate support 107 includes a bias electrode112 for generating an electric field to attract ions toward thesubstrate support 107, and thereby toward the substrate 105 held on thesubstrate support 107. Also, in one embodiment, the substrate support107 includes a number of cooling channels 116 through which a coolingfluid can be flowed during plasma processing operations to maintaintemperature control of the substrate 105. Also, in one embodiment, thesubstrate support 107 can include a number of lifting pins defined tolift and lower the substrate 105 relative to the substrate support 107.In one embodiment, the substrate support 107 is defined as anelectrostatic chuck equipped to generate an electrostatic field forholding the substrate 105 securely on the substrate support 107 duringplasma processing operations.

In various embodiments, the first and second plasma chambers 101/102 aredefined to operate in either a simultaneous manner or a pulsed manner.Operation of the first and second plasma chambers 101/102 in the pulsedmanner includes either the first plasma chamber 101 or the second plasmachamber 102 operating at a given time and in an alternating sequence.Specifically, the first plasma chamber 101 will operate for a firstperiod of time with the second plasma chamber 102 idle, then the secondplasma chamber 102 will operate for a second period of time with thefirst plasma chamber 101 idle, with the first and second plasma chambers101/102 operating in this alternating manner for a prescribed totalperiod of time.

Operation of the first and second plasma chambers 101/102 in the pulsedmanner can serve to prevent/limit undesirable communication between thefirst and second plasmas 101A/102A with regard to process gas and/orpower. Prevention of undesirable communication between the first andsecond plasma chambers 101/102 includes ensuring that processgases/species of the first plasma 101A do not enter the second plasmachamber 102, and ensuring that the process gases/species of the secondplasma 102A do not enter the first plasma chamber 101. Prevention ofundesirable communication between the first and second plasma chambers101/102 also includes ensuring that power supplied to the first plasmachamber 101 does not flow to the second plasma 102A in the second plasmachamber, and ensuring that power supplied to the second chamber 102 doesnot flow to the first plasma 101A in the first plasma chamber 101.

In the embodiments where the first and second plasma chambers 101/102are operated in a simultaneous manner, the first and second plasmachambers 101/102 are defined to ensure that undesirable communicationtherebetween is prevented/limited. For example, the respective openingsof the first and second plasma chambers 101/102 in exposure to theprocessing region 106 are sized small enough and spaced apart far enoughto avoid cross-communication between the first and second plasmachambers 101/102 with regard to process gas and/or power. Based on theforegoing, it should be understood that the first and second plasmachambers 101/102 can be independently controlled during a substrateplasma process with regard to one or more of process gas flow rate,process gas pressure, power frequency, power amplitude, on/off duration,and operational timing sequence.

FIG. 2B shows a semiconductor substrate processing system 200B, inaccordance with one embodiment of the present invention. The system 200Bis a variation of the system 200A of FIG. 2A. Specifically, the system200B includes a baffle structure 109 disposed between the first andsecond plasma chambers 101/102 to extend from the first and secondplasma chambers 101/102 toward the substrate support 107. The bafflestructure 109 is defined to reduce fluid communication between the firstand second plasma chambers 101/102. Also, in one embodiment, the bafflestructure 109 is formed from a dielectric materials so as to reducepower communication between the first and second plasma chambers101/102. In one embodiment, the baffle structure 109 is defined to bemovable in a direction 114 substantially perpendicular to a top surfaceof the substrate support 107 upon which the substrate 105 is to besupported.

FIG. 2C shows a semiconductor substrate processing system 200C, inaccordance with one embodiment of the present invention. The system 200Cis a variation of the system 200B of FIG. 2B. Specifically, the system200C includes an exhaust channel 111 formed between the first and secondplasma chambers 101/102 to extend away from the processing region 106 ina direction substantially perpendicular to a top surface of thesubstrate support 107 upon which the substrate 105 is to be supported.In one embodiment, the exhaust channel 111 is open and clear to providefor exhaust of gases from the processing region 106. However, in anotherembodiment, the baffle structure 109 is disposed within the exhaustchannel 111 between the first and second plasma chambers 101/102, so asto extend from the first and second plasma chambers 101/102 toward thesubstrate support 107. The baffle structure 109 disposed within theexhaust channel 111 is defined to reduce fluid communication between thefirst and second plasma chambers 101/102. Also, in one embodiment, thebaffle structure 109 disposed within the exhaust channel 111 is formedfrom a dielectric material so as to reduce power communication betweenthe first and second plasma chambers 101/102. Also, the baffle structure109 is sized smaller than the exhaust channel 111 so as to provide forexhaust flow 116 through the exhaust channel 111 around the bafflestructure 109.

In the example embodiments of FIGS. 2B and 2C, the baffle structure 109can be used to limit fluid and/or power communication between adjacentplasma chambers, e.g., 101, 102. Additionally, the baffle structure 109can be used to assist with establishing uniformity of ions and radicalsacross the substrate 105. As mentioned with regard to FIGS. 2B and 2C,the baffle structure 109 is movable in the direction 114 substantiallyperpendicular to the substrate support 107. This movement of the bafflestructure 109 in the direction 114 enables adjustment of a distance 115as measured perpendicularly between the baffle structure 109 and thesubstrate 105.

In various embodiments, the distance 115 between the baffle structureand the substrate 105 can be up to 5 cm. It should be understood,however, that the distance 115 is a function of other parameters such asprocess gas flow rates and ion and radical fluxes emanating from thefirst and second plasma chambers 101/102. In one example embodiment, thedistance 115 between the baffle structure and the substrate 105 is about2 cm. Additionally, although the baffle structure 109 as shown in theexample embodiments of FIGS. 2B and 2D is rectangular shaped incross-section, it should be understood that the baffle structure 109 canbe shaped in other ways, e.g., rounded bottom, angled bottom, taperedtop, etc, so as to achieve particular effects within the processingregion 106, such as controlling process gas flow conditions includingcross-flow and turbulence, among others.

In some situations, radical generation within a plasma in unavoidablewhen attempting to generate primarily ions within the plasma. In thesesituation, radical constituent transport from a generated plasma is alsosomewhat unavoidable when the primary objective is to achieve ionconstituent transport from the plasma. Furthermore, extracting ions froma plasma infers that the opening between the ion source, i.e., theplasma, and the processing region, e.g., processing region 106, be largeenough that a sheath does not inhibit plasma extraction and thatcollisions with the extracting medium walls are low so as not toneutralize the ions. In one embodiment of the present invention, an ionsource region can be defined in the opening between the ion source andthe processing region. This ion source region can be implemented as anenergized outlet region to provide supplemental electron generation toenhance ion extraction from the ion source. For example, in oneembodiment, the outlet region of the plasma chamber that is in exposureto the processing region can be defined as a hollow cathode to enhanceion generation within the outlet region itself and correspondinglyenhance ion extraction from the plasma chamber.

FIG. 2D shows a variation of the second plasma chamber 102A having anenergized outlet region 225 to enhance ion extraction, in accordancewith one embodiment of the present invention. It should be understood,however, that one or both of the first and second plasma chambers101/102 can be defined to have the energizable plasma outlet region 225defined to provide supplemental electron generation to increase ionextraction. In one embodiment, the energizable plasma outlet region 225is defined as hollow cathode. In one version of this embodiment, theoutlet region 225 is circumscribed by an electrode 220 that can be powerby either DC power, RF power, or a combination thereof. As the reactiveconstituents from the plasma 102A flow through the energizable plasmaoutlet region 225, the power emanating from the electrode 220 willliberate fast electrons within the outlet region 225, which will in turncause further ionization in the process gases flowing through the outletregion 225, thereby enhancing ion extraction from the plasma chamber102. Additionally, the bias applied across the processing region 106 bythe bias electrode 112 will serve to draw ions from both the plasma 102Awithin the chamber 102 and from the outlet region 225 toward thesubstrate 105.

FIG. 3A shows a vertical cross-section of a semiconductor substrateprocessing system 400, in accordance with one embodiment of the presentinvention. The system 400 includes a chamber 401 fanned by a topstructure 401B, a bottom structure 401C, and sidewalls 401A extendingbetween the top structure 401B and bottom structure 401C. The chamber401 encloses the processing region 106. In various embodiments, thechamber sidewalls 401A, top structure 401B, and bottom structure 401Ccan be formed from different materials, such as stainless steel oraluminum, by way of example, so long as the chamber 401 materials arestructurally capable of withstanding pressure differentials andtemperatures to which they will be exposed during plasma processing, andare chemically compatible with the plasma processing environment.

The system 400 also includes the substrate support 107 disposed withinthe chamber 401 and defined to support the substrate 105 in exposure tothe processing region 106. The substrate support 107 is defined to holdthe substrate 105 thereon during performance of a plasma processingoperation on the substrate 105. In the example embodiment of FIG. 3A,the substrate support 107 is held by a cantilevered arm 405 affixed to awall 401A of the chamber 401. However, in other embodiments, thesubstrate support 107 can be affixed to the bottom plate 401C of thechamber 401 or to another member disposed within the chamber 401. Invarious embodiments, the substrate support 107 can be formed fromdifferent materials, such as stainless steel, aluminum, or ceramic, byway of example, so long as the substrate support 107 material isstructurally capable of withstanding pressure differentials andtemperatures to which it will be exposed during plasma processing, andis chemically compatible with the plasma processing environment.

In one embodiment, the substrate support 107 includes the bias electrode112 for generating an electric field to attract ions toward thesubstrate support 107, and thereby toward the substrate 105 held on thesubstrate support 107. Also, in one embodiment, the substrate support107 includes the number of cooling channels 116 through which a coolingfluid can be flowed during plasma processing operations to maintaintemperature control of the substrate 105. Also, in one embodiment, thesubstrate support 107 can include a number of lifting pins 411 definedto lift and lower the substrate 105 relative to the substrate support107. In one embodiment, a door assembly 413 is disposed within thechamber wall 401A to enable insertion and removal of the substrate 105into/from the chamber 401. Additionally, in one embodiment, thesubstrate support 107 is defined as an electrostatic chuck equipped togenerate an electrostatic field for holding the substrate 105 securelyon the substrate support 107 during plasma processing operations.

The system 400 further includes a top plate assembly 407 disposed withinthe chamber 401 above and spaced apart from the substrate support 107,so as to be positioned above and spaced apart from the substrate 105when positioned on the substrate support 107. The substrate processingregion 106 exists between the top plate assembly 407 and the substratesupport 107, so as to exist over the substrate 105 when positioned onthe substrate support 107. As previously mentioned, in one embodiment,the substrate support 107 is movable in the direction 110 such that theprocess gap distance, as measured perpendicularly across the processingregion 106 between the top plate assembly 407 and substrate support 107is adjustable within a range extending from about 2 cm to about 10 cm.Also, in one embodiment, a vertical position of the substrate support107 relative to the top plate assembly 407, vice-versa, is adjustableeither during performance of the plasma processing operation or betweenplasma processing operations.

The top plate assembly 407 has a lower surface exposed to the processingregion 106 and opposite the top surface of the substrate support 107.The top plate assembly 407 includes a first plurality of plasma portsconnected to supply reactive constituents of the first plasma 101A tothe processing region 106. More specifically, in the embodiment of FIG.3A, a first plurality of plasma microchambers 101 are disposed acrossthe top surface of the top plate assembly 407, and the first pluralityof plasma ports are in fluid communication with respective openings ofthe first plurality of plasma microchambers 101. Thus, the firstplurality of plasma ports serve to place the openings of the firstplurality of plasma microchambers 101 in fluid communication with theprocessing region 106. It should be understood that each of the firstplurality of plasma microchambers corresponds to the first plasmachamber 101, as previously discussed with regard to FIGS. 1 through 2G.

The top plate assembly 407 also includes a second plurality of plasmaports connected to supply reactive constituents of the second plasma102A to the processing region 106. More specifically, in the embodimentof FIG. 3A, a second plurality of plasma microchambers 102 are disposedacross the top surface of the top plate assembly 407, and the secondplurality of plasma ports are in fluid communication with respectiveopenings of the second plurality of plasma microchambers 102. Thus, thesecond plurality of plasma ports serve to place the openings of thesecond plurality of plasma microchambers 102 in fluid communication withthe processing region 106. It should be understood that each of thesecond plurality of plasma microchambers corresponds to the secondplasma chamber 102, as previously discussed with regard to FIGS. 1through 2G.

Each of the first plurality of plasma microchambers 101 is defined togenerate the first plasma 101A and supply reactive constituents 108A ofthe first plasma 101A to one or more of the first plurality of plasmaports defined along the lower surface of the top plate assembly 407.Similarly, each of the second plurality of plasma microchambers 102 isdefined to generate the second plasma 102A and supply reactiveconstituents 108B of the second plasma 102A to one or more of the secondplurality of plasma ports defined along the lower surface of the topplate assembly 407.

FIG. 3B shows a horizontal cross-section view A-A as referenced in FIG.3A, in accordance with one embodiment of the present invention. As shownin FIG. 3B, the first and second plasma microchambers 101/102 areinterspersed among each other across the top plate assembly 407, suchthat the first plurality of plasma ports are interspersed among thesecond plurality of plasma ports in a substantially uniform manneracross the lower surface of the top plate assembly 407. In one exampleembodiment, the first and second plasma microchambers 101/102 aredefined to have an internal diameter within a range extending from about1 cm to about 2 cm. Also, in one example embodiment, a total number ofthe first and second plasma microchambers 101/102 is about 100. In yetanother example embodiment, a total number of the first and secondplasma microchambers 101/102 is within a range extending from about 40to about 60, and a total number of the first and second plasma portsacross the lower surface of the top plate assembly 407 is about 100.

It should be appreciated that the spacing between the first and secondplasma microchambers 101/102 across the top plate assembly 407 can bevaried among different embodiments. FIG. 3C shows a variation of thehorizontal cross-section view of FIG. 3B in which the spacing betweenthe first and second plasma microchambers 101/102 across the top plateassembly 407 is decreased, in accordance with one embodiment of thepresent invention. FIG. 3D shows a variation of the horizontalcross-section view of FIG. 3B in which the spacing between the first andsecond plasma microchambers 101/102 across the top plate assembly 407 isincreased, in accordance with one embodiment of the present invention.FIG. 3E shows a variation of the horizontal cross-section view of FIG.3B in which the spacing between the first and second plasmamicrochambers 101/102 across the top plate assembly 407 is non-uniform,in accordance with one embodiment of the present invention.

It should be understood that the above-mentioned example embodiments forthe number of first and second plasma microchambers 101/102 and/or thenumber of plasma ports in the lower surface of the top plate assembly407, are provided to facilitate description of the present invention anddo not represent limitations of the present invention in any way. Inother embodiments, essentially any configuration/number of first andsecond plasma microchambers 101/102 and/or plasma ports in the lowersurface of the top plate assembly 407 can be defined and arranged, asnecessary, to provide an appropriate mixture of radical and ionconstituents within the processing region 106, so as to achieve adesired plasma processing result on the substrate 105.

The first and second plasma microchambers 101/102 are defined to operatein either a simultaneous manner or a pulsed manner. Operation of thefirst and second plasma microchambers 101/102 in the pulsed mannerincludes either the first plurality of plasma microchambers 101 or thesecond plurality of plasma microchambers 102 operating at a given timeand in an alternating sequence. In one embodiment, each of the firstplurality of plasma microchambers 101 is either a hollow cathodechamber, or an electron cyclotron resonance chamber, or a microwavedriven chamber, or an inductively coupled chamber, or a capacitivelycoupled chamber. Also, in one embodiment, each of the second pluralityof plasma microchambers 102 is either a hollow cathode chamber, or anelectron cyclotron resonance chamber, or a microwave driven chamber, oran inductively coupled chamber, or a capacitively coupled chamber.

In one example embodiment, the plasma microchambers (101 or 102) thatare primarily responsible for radical constituent supply to theprocessing region 106 are defined as microwave driven plasmamicrochambers. Also, in one example embodiment, the plasma microchambers(101 or 102) that are primarily responsible for ion constituent supplyto the processing region 106 are defined as either hollow cathode plasmamicrochambers, electron cyclotron resonance plasma microchambers,capacitively coupled plasma microchambers, or a type of resonantdischarge plasma microchamber. In one particular example embodiment,each of the first plurality of plasma microchambers 101 is defined as aninductively coupled plasma microchamber 101 that is primarilyresponsible for supplying radical constituents to the processing region106. Also, in this particular example embodiment, each of the secondplurality of plasma microchambers 102 is defined as a capacitivelycoupled plasma microchamber 102 that is primarily responsible forsupplying ion constituents to the processing region 106.

It should be understood that the above-mentioned example embodiments forthe types of first and second plasma microchambers 101/102 are providedto facilitate description of the present invention and do not representlimitations of the present invention in any way. In other embodiments,the first and second plasma microchambers 101/102 can be respectivelydefined as essentially any type of plasma microchamber, or combinationof types of plasma microchambers, so long as the first and second plasmamicrochambers 101/102 are defined to supply the type(s) of reactiveconstituent(s) to the processing region 106 that they are primarilyresponsible for supplying, so as to achieve a desired plasma processingresult on the substrate 105.

The system 400 further includes a first power supply 103A defined tosupply a first power to the first plurality of plasma microchambers 101.The system 400 also includes a first process gas supply 104A defined tosupply a first process gas to the first plurality of plasmamicrochambers 101. The system 400 also includes a second power supply103B defined to supply a second power to the second plurality of plasmamicrochambers 102. The system 400 also includes a second process gassupply 104B defined to supply a second process gas to the secondplurality of plasma microchambers 102. In one embodiment, the first andsecond power supplies 103A/103B are independently controllable. In oneembodiment, the first and second process gas supplies 104A/104B areindependently controllable. In one embodiment, both the first and secondpower supplies 103A/103B, and the first and second process gas supplies104A/104B are independently controllable. In one embodiment, the firstpower that is supplied to the first plurality of plasma microchambers101 is either DC power, RF power, or a combination of DC and RF power.Also, in one embodiment, the second power that is supplied to the secondplurality of plasma microchambers 102 is either DC power, RF power, or acombination of DC and RF power.

With regard to supply of RF power by either of the first and secondpower supplies 103A/103B, it should be understood that the supplied RFpower can be independently controllable with regard to RF powerfrequency and/or amplitude. Also, it should be understood that each ofthe first and second power supplies 103A/103B includes respectivematching circuitry through which its RF power is transmitted to ensureefficient RF power transmission to the first and second pluralities ofplasma microchambers 101/102, respectively. In one embodiment, the firstpower supplied by the first power supply 103A to each of the firstplurality of plasma microchambers 101 is RF power having a frequency ofeither 2 MHz, 27 MHz, 60 MHz, or 400 kHz, and the second power suppliedby the second power supply 103B to each of the second plurality ofplasma microchambers 102 is RF power having a frequency of either 2 MHz,27 MHz, 60 MHz, or 400 kHz. In this embodiment, the first and secondpowers have at least one different frequency.

During operation of the system 400, the process gases supplied by thefirst and second process gas supplies 104A/104B are transformed into thefirst and second plasmas 101A/102A, respectively, within each of thefirst and second pluralities of plasma microchambers 101/102. Reactivespecies within the first and second plasmas 101A/102A move from thefirst and second pluralities of plasma microchambers 101/102 to thesubstrate processing region 106 over the substrate support 107, i.e.,onto the substrate 105 when disposed on the substrate support 107.

In one embodiment, upon entering the substrate processing region 106from the first and second pluralities of plasma microchambers 101/102,the used process gas flows through peripheral vents 427, and is pumpedout through exhaust ports 429 by an exhaust pump 431. In one embodiment,a flow throttling device 433 is provided to control a flow rate of theused process gas from the substrate processing region 106. In oneembodiment, the flow throttling device 433 is defined as a ringstructure that is movable toward and away from the peripheral vents 427,as indicated by arrows 435.

It should be appreciated that the system 400 utilizes a large number ofsmall plasma sources of one type, i.e., the first plurality of plasmamicrochambers 101, interspersed among a large number of small plasmasources of another type, i.e., the second plurality of plasmamicrochambers 102, in order to deliver a combined reactive constituentflux from each type of plasma source in a substantially uniform mannerto the substrate 105. In one embodiment, one type of plasma sourcegenerates a larger density of radical constituents relative to ionconstituents, and the other type of plasma source generates a largerdensity of ion constituents relative to radical constituents, therebyproviding independent control of ion and radical concentrations withinthe processing region 106.

FIG. 4A shows another system 500 for substrate plasma processing, inaccordance with one embodiment of the present invention. The system 500is essentially equivalent to the system 400 of FIG. 3A with regard tothe chamber 401, the substrate support 107, the peripheral vents 427,the flow throttling device 433, the exhaust ports 429, and the exhaustpump 431. However, the system 500 includes a variation on the first andsecond pluralities of plasma microchambers 101/102 disposed across thetop plate assembly 407A, as previously discussed with regard to FIG. 3A.Specifically, rather than including many instances of the first andsecond plasma microchambers 101/102 to supply their respective reactiveconstituents to the plasma ports in the top plate assembly 407, thesystem 500 includes a large first plasma chamber 501 defined to generatethe first plasma 101A and supply reactive constituents of the firstplasma 101A to each of a first plurality of plasma ports within the topplate assembly 407. Similarly, the system 500 includes a large secondplasma chamber 502 defined to generate the second plasma 102A and supplyreactive constituents of the second plasma 102A to each of a secondplurality of plasma ports within the top plate assembly 407.

In one embodiment, the system 500 includes a single instance of thefirst plasma chamber 501 to supply reactive constituents of the firstplasma 101A to the processing region 106. Also, in this embodiment, thesystem 500 includes a single instance of the second plasma chamber 501to supply reactive constituents of the second plasma 102A to theprocessing region 106. In other embodiments, the system 500 can includemore than one instance of the first plasma chamber 501 to supplyreactive constituents of the first plasma 101A to the processing region106, wherein each instance of the first plasma chamber 501 is fluidlyconnected to multiple plasma ports within the top plate assembly 407.Similarly, in other embodiments, the system 500 can include more thanone instance of the second plasma chamber 502 to supply reactiveconstituents of the second plasma 102A to the processing region 106,wherein each instance of the second plasma chamber 502 is fluidlyconnected to multiple plasma ports within the top plate assembly 407.

Also, it should be understood that the characteristics and operationalconditions previously discussed with regard to the first plasma chamber101 of FIGS. 2A-2D are equally applicable to the first plasma chamber501. Also, it should be understood that the characteristics andoperational conditions previously discussed with regard to the secondplasma chamber 102 of FIGS. 2A-2D are equally applicable to the secondplasma chamber 502.

The plasma ports within the top plate assembly 407 that are fluidlyconnected to the first plasma chamber 501 are interspersed across thetop plate assembly 407 in a substantially uniform manner with the plasmaports within the top plate assembly 407 that are fluidly connected tothe second plasma chamber 502. FIG. 4B shows a horizontal cross-sectionview B-B as referenced in FIG. 4A, in accordance with one embodiment ofthe present invention. As shown in FIG. 4B, the outputs of the first andsecond plasma chambers 501/502 are interspersed among each other acrossthe top plate assembly 407 in a substantially uniform manner.

It should be appreciated that the spacing between the plasma portsassociated with the first and second plasma chambers 501/502 across thetop plate assembly 407 can be varied among different embodiments. FIG.4C shows a variation of the horizontal cross-section view of FIG. 4B inwhich the spacing between the plasma ports associated with the first andsecond plasma chambers 501/502 across the top plate assembly 407 isdecreased, in accordance with one embodiment of the present invention.FIG. 4D shows a variation of the horizontal cross-section view of FIG.4B in which the spacing between the plasma ports associated with thefirst and second plasma chambers 501/502 across the top plate assembly407 is increased, in accordance with one embodiment of the presentinvention. FIG. 4E shows a variation of the horizontal cross-sectionview of FIG. 4B in which the spacing between the plasma ports associatedwith the first and second plasma chambers 501/502 across the top plateassembly 407 is non-uniform, in accordance with one embodiment of thepresent invention.

In one embodiment, the first plasma chamber 501 is primarily responsiblefor supplying radical constituents to the processing region 106, and thesecond plasma chamber 502 is primarily responsible for supplying ionconstituents to the processing region 106. In this embodiment, the largeplasma generation volume of the first plasma chamber 501 is used to feedmultiple radical constituent dispense ports within the top plateassembly 407. Also, in this embodiment, the large plasma generationvolume of the second plasma chamber 502 is used to feed multiple ionconstituent dispense ports within the top plate assembly 407. In thisembodiment, the multiple radical and ion dispense ports are interspersedwith each other to provide a substantially uniform radical/ion mixturewithin the processing region 106.

The system 500 also includes the first power supply 103A defined tosupply power to the first plasma chamber 501, and the first process gassupply 104A defined to supply process gas to the first plasma chamber.Also, the system 500 includes the second power supply 103B defined tosupply power to the second plasma chamber 502, and the second processgas supply 104B defined to supply process gas to the second plasmachamber 502. As with the system 400, in the system 500, either the firstand second power supplies 103A/103B are independently controllable, orthe first and second process gas supplies 104A/104B are independentlycontrollable, or both the first and second power supplies 103A/103B andthe first and second process gas supplies 104A/104B are independentlycontrollable. Additionally, in one embodiment, the first and secondplasma chambers 501/502 of the system 500 are defined to operate ineither a simultaneous manner or a pulsed manner. When operated in thepulsed manner, either the first plasma chamber 501 or the second plasmachamber 502 is operated at a given time, and the first and second plasmachambers 501/502 are operated in an alternating sequence.

FIG. 5A shows another system 600 for substrate plasma processing,accordance with one embodiment of the present invention. The system 600is essentially equivalent to the system 400 of FIG. 3A with regard tothe chamber 401 and the substrate support 107. However, the system 600replaces the top plate assembly 407, as previously discussed with regardto FIG. 3A, with a top plate assembly 601 that includes a first set ofplasma microchambers 605 and a second set of plasma microchambers 603formed within exhaust channels 607.

The system 600 includes the chamber 401 having the top structure 401B,the bottom structure 401C, and the sidewalls 401A extending between thetop and bottom structures 401B/401C. The chamber 401 also includes theprocessing region 106. The substrate support 107 is disposed within thechamber 401 and has a top surface defined to support the substrate 105in exposure to the processing region 106. The top plate assembly 601 isdisposed within the chamber 401 above the substrate support 107. The topplate assembly 601 has a lower surface exposed to the processing region106 and opposite the top surface of the substrate support 107.

The top plate assembly 601 includes the first set of plasmamicrochambers 605 each formed into the lower surface of the top plateassembly 601. The top plate assembly 601 also includes a first networkof gas supply channels 611 formed to flow a first process gas from thefirst gas supply 104A to each of the first set of plasma microchambers605. Supply of the first process gas to the first network of gas supplychannels 611 is indicated by lines 611A in FIG. 5A. Each of the firstset of plasma microchambers 605 is connected to receive power from thefirst power supply 103A, and is defined to use this received power totransform the first process gas into a first plasma in exposure to theprocessing region 106. Supply of the first power to the first set ofplasma microchambers 605 is also indicated by lines 611A in FIG. 5A.

A first set of power delivery components 615 are respectively disposedwithin the top plate assembly 601 about the first set of plasmamicrochambers 605. Each of the first set of power delivery components615 is connected to receive the first power from the first power supply103A and supply the first power to its associated one of the first setof plasma microchambers 605. In one embodiment, each of the first set ofpower delivery components 615 is defined as a coil formed tocircumscribe a given one of the first set of plasma microchambers 605.However, it should be understood that in other embodiments the first setof power delivery components 615 can be defined in ways other than acoil. For example, in one embodiment, each of the first set of powerdelivery components 615 is defined as one or more electrodes configuredand disposed to convey the first power to its associated one of thefirst set of plasma microchambers 605.

The top plate assembly 601 also includes the set of exhaust channels 607formed through the lower surface of the top plate assembly 601 toprovide for removal of exhaust gases from the processing region 106.Each exhaust channel 607 is fluidly connected to an exhaust fluidconveyance system 607A, such as channels, tubing, plenum(s), and thelike, which is in turn fluidly connected to an exhaust pump 619. Whenoperated, the exhaust pump 619 applies a suction through the exhaustfluid conveyance system 607A to the set of exhaust channels 607 toremove process gases from the processing region 106. As indicated byarrows 617, the process gases that flow into the processing region 106through the first set of plasma microchambers 605 are drawn toward andinto the exhaust channels 607.

The second set of plasma microchambers 603 are respectively formedinside the set of exhaust channels 607. A second network of gas supplychannels 609 is formed to flow a second process gas from the secondprocess gas supply 104B to each of the second set of plasmamicrochambers 603. Supply of the second process gas to the secondnetwork of gas supply channels 609 is indicated by lines 609A in FIG.5A. Each of the second set of plasma microchambers 603 is connected toreceive power from the second power supply 103B, and is defined to usethis received power to transform the second process gas into a secondplasma in exposure to the processing region 106. Supply of the secondpower to the second set of plasma microchambers 603 is also indicated bylines 609A in FIG. 5A.

A second set of power delivery components 613 are respectively disposedwithin the top plate assembly 601 about the second set of plasmamicrochambers 603. Each of the second set of power delivery components613 is connected to receive the second power from the second powersupply 103B and supply the second power to its associated one of thesecond set of plasma microchambers 603. In one embodiment, each of thesecond set of power delivery components 613 is defined as a coil formedto circumscribe a given one of the second set of plasma microchambers603. However, it should be understood that in other embodiments thesecond set of power delivery components 613 can be defined in ways otherthan a coil. For example, in one embodiment, each of the second set ofpower delivery components 613 is defined as one or more electrodesconfigured and disposed to convey the second power to its associated oneof the second set of plasma microchambers 603.

The electrode 112 within the substrate support 107 is defined to apply abias voltage across the processing region 106 between the substratesupport 107 and the lower surface of the top plate assembly 601. Theprocess gases that flow through the second network of gas supplychannels 609 into the second set of plasma microchambers 603, i.e., intothe exhaust channels 607, are drawn away from the processing region 106and do not enter the processing region 106. Therefore, because thesecond set of plasma microchambers 603 are formed within the exhaustchannels 607, the radicals formed within the second set of plasmamicrochambers 603 will follow the exhaust gas flow path through theexhaust channels 607. However, the ions formed within the second set ofplasma microchambers 603 will be pulled into the processing region 106by the bias voltage applied across the processing region 106 by theelectrode 112. In this manner, the second set of plasma microchambers603 can operate as a substantially pure ion source for the processingregion 106.

It should be understood that the first set of plasma microchambers 605are interspersed with the second set of plasma microchambers 603 in asubstantially uniform manner across the lower surface of the top plateassembly 601. In this manner, the reactive radical constituents from thefirst set of plasma microchambers 605 can be mixed in a substantiallyuniform manner with the ion constituents from the second set of plasmamicrochambers 603 within the processing region 106 prior to reaching thesubstrate 105. FIG. 5B shows a horizontal cross-section view C-C asreferenced in FIG. 5A, in accordance with one embodiment of the presentinvention. As shown in FIG. 5B, the first and second sets of plasmamicrochambers 605/603 are distributed in a substantially uniform manneracross the lower surface of the top plate assembly 601.

It should be appreciated that the spacing between the first and secondsets of plasma microchambers 605/603 across the lower surface of the topplate assembly 601 can be varied among different embodiments. FIG. 5Cshows a variation of the horizontal cross-section view of FIG. 5B inwhich the spacing between the first and second sets of plasmamicrochambers 605/603 across the lower surface of the top plate assembly601 is decreased, in accordance with one embodiment of the presentinvention. FIG. 5D shows a variation of the horizontal cross-sectionview of FIG. 5B in which the spacing between the first and second setsof plasma microchambers 605/603 across the lower surface of the topplate assembly 601 is increased, in accordance with one embodiment ofthe present invention. FIG. 5E shows a variation of the horizontalcross-section view of FIG. 5B in which the spacing between the first andsecond sets of plasma microchambers 605/603 across the lower surface ofthe top plate assembly 601 is non-uniform, in accordance with oneembodiment of the present invention.

As with the embodiments of FIGS. 2A-2G, 3A-3E, 4A-4E, in the embodimentsof FIGS. 5A-5E, the first and second power supplies 103A/103B and thefirst and second gas supplies 104A/104B can be controlled in a varietyof ways. In one embodiment, the first and second power supplies103A/103B are independently controllable. In one embodiment, the firstand second process gas supplies 104A/104B are independentlycontrollable. In yet another embodiment, both the first and second powersupplies 103A/103B and the first and second process gas supplies104A/104B are independently controllable. In following, it should beunderstood that the first and second sets of plasma microchambers605/603 are defined to operate in either a simultaneous manner or apulsed manner. When operated in the pulsed manner, either the first setof plasma microchambers 605 or the second set of plasma microchambers603 is operated at a given time, and the first and second sets of plasmamicrochambers 605/603 are operated in an alternating sequence.

Given the embodiment of FIG. 5A, it should be appreciated that thedrivers which allow a plasma to escape from its generation region, e.g.,ambipolar diffusion, can be made opposite the drivers which allowradicals to escape into the plasma region by reversing the process gasflow direction. Adding top pumping to the ion sources, i.e., to thesecond set of plasma microchambers 603, facilitates both more efficiention extraction (wider openings) and a larger ion/neutral flux ratio fromthe plasma source itself. Additionally, it should be understood that inone embodiment the chamber 401 of FIG. 5A can be further equipped withthe peripheral vents 427, flow throttling device 433, exhaust ports 429,and exhaust pump 431, as previously described with regard to theembodiments of FIGS. 3A and 4A, to enable peripheral exhaust flow inaddition to the top exhaust flow through the exhaust channels 607.

In the various embodiments disclosed herein, the different ion andradical plasma sources can be process controlled with regard to gasflow, gas pressure, power frequency, power amplitude, on duration, offduration, and timing sequence. Also, the different types of plasmasources can be pulsed to mitigate communication between neighboringplasma sources. The two different plasma source types can also beoperated using different gas mixtures in order to achieve a condition ofa higher flux of ions from one plasma source and a higher flux ofradicals from the other plasma source. With the mixed array of ion andradical plasma sources, in one embodiment, each plasma source can beconnected to its own separately controlled power and gas supplies. Also,in another embodiment, all ion plasma sources in the mixed array can beconnected to a common gas supply and a common power supply, and allradical plasma source in the mixed array can be connected to anothercommon gas supply and another common power supply.

In one embodiment, the system 600 of FIG. 5A represents a semiconductorsubstrate processing system having a plate assembly 601 that has aprocess-side surface exposed to the plasma processing region 601. Theplate assembly 601 includes an exhaust channel 607 formed through theprocess-side surface of the plate assembly 601 to provide for removal ofexhaust gases from the plasma processing region 601. The plasmamicrochamber 603 is formed inside the exhaust channel. The gas supplychannel 609 is formed through the plate assembly 601 to flow a processgas to the plasma microchamber 603 in the exhaust channel 607. A powerdelivery component 613 is fowled within the plate assembly 601 totransmit power to the plasma microchamber region 603, so as to transformthe process gas into a plasma within the plasma microchamber 603 in theexhaust channel 607.

In one embodiment, the power supplied to the power delivery component613 is either DC power, RF power, or a combination of DC and RF power.In one embodiment, the power supplied to the power delivery component613 is RF power having a frequency of either 2 MHz, 27 MHz, 60 MHz, or400 kHz. In one embodiment the power delivery component 613 is definedas a coil formed within the plate assembly 601 to circumscribe theplasma microchamber 603 in the exhaust channel 607.

The system 600 also includes an electrode 112 disposed outside of theplate assembly 601 that when energized causes ions to be attracted fromthe plasma microchamber 603 in the exhaust channel 607 into the plasmaprocessing region 106. In one embodiment, the electrode 112 is disposedwithin the substrate support 107, with the substrate support 107disposed to support the substrate 105 in exposure to the plasmaprocessing region 106. Also, in one embodiment, the exhaust channel 607is defined to remove gases from the processing region 106 in a directionsubstantially perpendicular to and away from a surface of the substratesupport 107 upon which the substrate 105 is to be supported.

FIG. 6 shows a flowchart of a method for processing a semiconductorsubstrate, in accordance with one embodiment of the present invention.The method includes an operation 701 for placing a substrate 105 on asubstrate support 107 in exposure to a processing region 106. The methodalso includes an operation 703 for generating a first plasma 101A of afirst plasma type. The method also includes an operation 705 forgenerating a second plasma 102A of a second plasma type different thanthe first plasma type. The method also includes an operation 707 forsupplying reactive constituents 108A/108B of both the first and secondplasmas 101A/102A to the processing region 106 to affect a processing ofthe substrate 105.

The method also includes operations for using a first power and a firstprocess gas to generate the first plasma 101A, and using a second powerand a second process gas to generate the second plasma 102A. In oneembodiment, the method includes an operation for independentlycontrolling either the first and second powers, or the first and secondprocess gases, or both the first and second powers and the first andsecond process gases. Also, in one embodiment, the first power is eitherDC power, RF power, or a combination of DC and RF power, and the secondpower is either DC power, RF power, or a combination of DC and RF power.In one example embodiment, the first power is RF power having a firstfrequency of either 2 MHz, 27 MHz, 60 MHz, or 400 kHz, and the secondpower is RF power having a second frequency of either 2 MHz, 27 MHz, 60MHz, or 400 kHz, with the second frequency being different than thefirst frequency.

In the method, the first plasma 101A is generated to have a first ratioof ion density to radical density, and the second plasma 102A isgenerated to have a second ratio of ion density to radical density. Thesecond ratio of ion density to radical density in the second plasma 102Ais different than the first ratio of ion density to radical density inthe first plasma 101A. In the method, reactive constituents from boththe first and second plasmas 101A/102A are supplied in a substantiallyuniform manner throughout the processing region 106 in exposure to thesubstrate 105. Also, in various embodiments, reactive constituents fromthe first and second plasmas 101A/102A are generated and supplied ineither a simultaneous manner or a pulsed manner. Generation and supplyof the first and second plasmas 101A/102A in the pulsed manner includesgeneration and supply of reactive constituents of either the firstplasma 101A or the second plasma 102A at a given time and in analternating sequence.

The method can also include an operation for generating supplementalelectrons to increase ion extraction from one or both of the first andsecond plasmas 101A/102A into the processing region 106, such asdescribed with regard to FIG. 2D. Also, the method can include anoperation for applying a bias voltage across the processing region 106from the substrate support 107, so as to attract ions from one or bothof the first and second plasmas 101A/102A toward the substrate 105, suchas described herein with regard to operation of the electrode 112.

Additionally, in one embodiment, the method can include an operation forpositioning a baffle structure 109 between a first port through whichreactive constituents of the first plasma 101A are supplied to theprocessing region 106 and a second port through which reactiveconstituents of the second plasma 102A are supplied to the processingregion 106. In this embodiment, the method can also include an operationfor controlling a position of the baffle structure 109 relative to thesubstrate support 107, so as to limit one or both of fluid communicationand power communication between the first and second ports through whichthe reactive constituents of the first and second plasma 101A/102A areemitted into the processing region 106.

FIG. 7 shows a flowchart of a method for processing a semiconductorsubstrate, in accordance with one embodiment of the present invention.The method includes an operation 801 for placing a substrate 105 on asubstrate support 107 in exposure to a processing region 106. The methodalso includes an operation 803 for operating a first set of plasmamicrochambers 605 in exposure to the processing region 106, whereby eachof the first set of plasma microchambers 605 generates a first plasmaand supplies reactive constituents of the first plasma to the processingregion 106. The first set of plasma microchambers 605 are located abovethe processing region 106 opposite from the substrate support 107. Themethod also includes an operation 805 for operating a second set ofplasma microchambers 603 in exposure to the processing region 106,whereby each of the second set of plasma microchambers 603 generates asecond plasma and supplies reactive constituents of the second plasma tothe processing region 106. The second plasma is different than the firstplasma. Also, the second set of plasma microchambers 603 are locatedabove the processing region 106 opposite from the substrate support 107,and are interspersed in a substantially uniform manner among the firstset of plasma microchambers 605.

The method further includes operations for supplying a first power tothe first set of plasma microchambers 605, supplying a first process gasto the first set of plasma microchambers 605, supplying a second powerto the second set of plasma microchambers 603, and supplying a secondprocess gas to the second set of plasma microchambers 603. In variousembodiments, the method includes an operation for independentlycontrolling either the first and second powers, or the first and secondprocess gases, or both the first and second powers and the first andsecond process gases. In one embodiment, the first power is either DCpower, RF power, or a combination of DC and RF power, and the secondpower is either DC power, RF power, or a combination of DC and RF power.In one example embodiment, the first power is RF power having a firstfrequency of either 2 MHz, 27 MHz, 60 MHz, or 400 kHz, and the secondpower is RF power having a second frequency of either 2 MHz, 27 MHz, 60MHz, or 400 kHz, with the second frequency being different than thefirst frequency.

The method further includes an operation for removing exhaust gases fromthe processing region 106 through a set of exhaust channels 607 definedto remove gases from the processing region 106 in a directionsubstantially perpendicular to and away from a top surface of thesubstrate support 107 upon which the substrate 105 is placed. In oneembodiment, the second set of plasma microchambers 603 are respectivelydefined inside the set of exhaust channels 607.

The method includes operating the first set of plasma microchambers 605to generate the first plasma to have a first ratio of ion density toradical density, and operating the second set of plasma microchambers603 to generate the second plasma to have a second ratio of ion densityto radical density, with the second ratio of ion density to radicaldensity in the second plasma being different than the first ratio of iondensity to radical density in the first plasma. Also, in the embodimentwhere the second set of plasma microchambers 603 are respectivelydefined inside the set of exhaust channels 607, the first plasma has ahigher radical density than ion density, and the second plasma has ahigher ion density than radical density.

In one embodiment, the method includes operation of the first and secondsets of plasma microchambers 605/603 in a simultaneous manner. Inanother embodiment, the first and second sets of plasma microchambers605/603 are operated in a pulsed manner in which either the first set ofplasma microchambers 605 or the second set of plasma microchambers 603are operated at a given time, and in which the first and second sets ofplasma microchambers 605/603 are operated in an alternating sequence.Additionally, the method can include an operation for applying a biasvoltage across the processing region 106 from the substrate support 107,so as to attract ions from one or both of the first and second plasmasrespectively generated within the first and second sets of plasmamicrochambers 605/603 toward the substrate 105, such as discussed hereinwith regard to the electrode 112.

While this invention has been described in terms of several embodiments,it will be appreciated that those skilled in the art upon reading thepreceding specifications and studying the drawings will realize variousalterations, additions, permutations and equivalents thereof. It istherefore intended that the present invention includes all suchalterations, additions, permutations, and equivalents as fall within thetrue spirit and scope of the invention.

1. A semiconductor substrate processing system, comprising: a substratesupport defined to support a substrate in exposure to a processingregion; a first plasma chamber defined to generate a first plasma andsupply reactive constituents of the first plasma to the processingregion; and a second plasma chamber defined to generate a second plasmaand supply reactive constituents of the second plasma to the processingregion, wherein the first and second plasma chambers are defined to beindependently controlled.
 2. A semiconductor substrate processing systemas recited in claim 1, further comprising: a first power supply definedto supply a first power to the first plasma chamber; a first process gassupply defined to supply a first process gas to the first plasmachamber; a second power supply defined to supply a second power to thesecond plasma chamber; and a second process gas supply defined to supplya second process gas to the second plasma chamber.
 3. A semiconductorsubstrate processing system as recited in claim 2, wherein either thefirst and second power supplies are independently controllable, or thefirst and second process gas supplies are independently controllable, orboth the first and second power supplies and the first and secondprocess gas supplies are independently controllable.
 4. A semiconductorsubstrate processing system as recited in claim 2, wherein the firstpower is either direct current (DC) power, radiofrequency (RF) power, ora combination of DC and RF power, and wherein the second power is eitherDC power, RF power, or a combination of DC and RF power.
 5. Asemiconductor substrate processing system as recited in claim 1, whereinthe first and second plasma chambers are defined to operate in either asimultaneous manner or a pulsed manner, wherein the pulsed mannerincludes either the first plasma chamber or the second plasma chamberoperating at a given time and in an alternating sequence.
 6. Asemiconductor substrate processing system as recited in claim 1, whereinthe substrate support is defined to be movable in a directionsubstantially perpendicular to a top surface of the substrate supportupon which the substrate is to be supported.
 7. A semiconductorsubstrate processing system as recited in claim 1, wherein one or bothof the first and second plasma chambers is defined to have anenergizable plasma outlet region defined to provide supplementalelectron generation to increase ion extraction.
 8. A semiconductorsubstrate processing system as recited in claim 2, wherein the substratesupport includes an electrode defined to apply a bias voltage across theprocessing region between the substrate support and the first and secondplasma chambers.
 9. A semiconductor substrate processing system asrecited in claim 1, further comprising: a baffle structure disposedbetween the first and second plasma chambers to extend from the firstand second plasma chambers toward the substrate support, wherein thebaffle structure is defined to reduce fluid communication between thefirst and second plasma chambers.
 10. A semiconductor substrateprocessing system as recited in claim 1, further comprising: an exhaustchannel formed between the first and second plasma chambers to extendaway from the processing region in a direction substantiallyperpendicular to a top surface of the substrate support upon which thesubstrate is to be supported.
 11. A semiconductor substrate processingsystem as recited in claim 10, further comprising: a baffle structuredisposed within the exhaust channel between the first and second plasmachambers so as to extend from the first and second plasma chamberstoward the substrate support, wherein the baffle structure is defined toreduce fluid communication between the first and second plasma chambers,and wherein the baffle structure is sized smaller than the exhaustchannel so as to provide for exhaust flow through the exhaust channelaround the baffle structure.
 12. A semiconductor substrate processingsystem, comprising: a chamber having a top structure, a bottomstructure, and sidewalls extending between the top and bottomstructures, wherein the chamber encloses a processing region; asubstrate support disposed within the chamber and defined to support asubstrate in exposure to the processing region; a top plate assemblydisposed within the chamber above the substrate support, the top plateassembly having a lower surface exposed to the processing region andopposite the top surface of the substrate support, the top plateassembly including a first plurality of plasma ports connected to supplyreactive constituents of a first plasma to the processing region, thetop plate assembly including a second plurality of plasma portsconnected to supply reactive constituents of a second plasma to theprocessing region.
 13. A semiconductor substrate processing system asrecited in claim 12, wherein the substrate support is defined to bemovable in a direction substantially perpendicular to a top surface ofthe substrate support upon which the substrate is to be supported.
 14. Asemiconductor substrate processing system as recited in claim 12,wherein the substrate support includes an electrode defined to apply abias voltage across the processing region between the substrate supportand the lower surface of the top plate assembly.
 15. A semiconductorsubstrate processing system as recited in claim 12, further comprising:a first plurality of plasma microchambers each defined to generate thefirst plasma and supply reactive constituents of the first plasma to oneor more of the first plurality of plasma ports; and a second pluralityof plasma microchambers each defined to generate the second plasma andsupply reactive constituents of the second plasma to one or more of thesecond plurality of plasma ports.
 16. A semiconductor substrateprocessing system as recited in claim 15, further comprising: a firstpower supply defined to supply a first power to the first plurality ofplasma microchambers; a first process gas supply defined to supply afirst process gas to the first plurality of plasma microchambers; asecond power supply defined to supply a second power to the secondplurality of plasma microchambers; and a second process gas supplydefined to supply a second process gas to the second plurality of plasmamicrochambers.
 17. A semiconductor substrate processing system asrecited in claim 16, wherein either the first and second power suppliesare independently controllable, or the first and second process gassupplies are independently controllable, or both the first and secondpower supplies and the first and second process gas supplies areindependently controllable.
 18. A semiconductor substrate processingsystem as recited in claim 12, further comprising: a first plasmachamber defined to generate the first plasma and supply reactiveconstituents of the first plasma to each of the first plurality ofplasma ports; and a second plasma chamber defined to generate the secondplasma and supply reactive constituents of the second plasma to each ofthe second plurality of plasma ports.
 19. A semiconductor substrateprocessing system as recited in claim 18, further comprising: a firstpower supply defined to supply a first power to the first plasmachamber; a first process gas supply defined to supply a first processgas to the first plasma chamber; a second power supply defined to supplya second power to the second plasma chamber; and a second process gassupply defined to supply a second process gas to the second plasmachamber.
 20. A semiconductor substrate processing system as recited inclaim 19, wherein either the first and second power supplies areindependently controllable, or the first and second process gas suppliesare independently controllable, or both the first and second powersupplies and the first and second process gas supplies are independentlycontrollable.
 21. A method for processing a semiconductor substrate,comprising: placing a substrate on a substrate support in exposure to aprocessing region; generating a first plasma of a first plasma type;generating a second plasma of a second plasma type different than thefirst plasma type; and supplying reactive constituents of both the firstand second plasmas to the processing region to affect a processing ofthe substrate.
 22. A method for processing a semiconductor substrate asrecited in claim 21, wherein the first plasma is generated to have afirst ratio of ion density to radical density, and wherein the secondplasma is generated to have a second ratio of ion density to radicaldensity, the second ratio of ion density to radical density in thesecond plasma being different than the first ratio of ion density toradical density in the first plasma.
 23. A method for processing asemiconductor substrate as recited in claim 21, further comprising:using a first power and a first process gas to generate the firstplasma; and using a second power and a second process gas to generatethe second plasma.
 24. A method for processing a semiconductor substrateas recited in claim 23, further comprising: independently controllingeither the first and second powers, or the first and second processgases, or both the first and second powers and the first and secondprocess gases.
 25. A method for processing a semiconductor substrate asrecited in claim 23, wherein the first power is either direct current(DC) power, radiofrequency (RF) power, or a combination of DC and RFpower, and wherein the second power is either DC power, RF power, or acombination of DC and RF power.
 26. A method for processing asemiconductor substrate as recited in claim 21, wherein reactiveconstituents from both the first and second plasmas are supplied in asubstantially uniform manner throughout the processing region inexposure to the substrate.
 27. A method for processing a semiconductorsubstrate as recited in claim 21, wherein reactive constituents from thefirst and second plasmas are generated and supplied in either asimultaneous manner or a pulsed manner, wherein the pulsed mannerincludes generation and supply of reactive constituents of either thefirst plasma or the second plasma at a given time and in an alternatingsequence.
 28. A method for processing a semiconductor substrate asrecited in claim 21, further comprising: generating supplementalelectrons to increase ion extraction from one or both of the first andsecond plasmas into the processing region.
 29. A method for processing asemiconductor substrate as recited in claim 21, further comprising:applying a bias voltage across the processing region from the substratesupport so as to attract ions from one or both of the first and secondplasmas toward the substrate.
 30. A method for processing asemiconductor substrate as recited in claim 21, further comprising:positioning a baffle structure between a first port through which thefirst plasma is supplied to the processing region and a second portthrough which the second plasma is supplied to the processing region.